> A have attached a schematic for iris control, please have a look with you=
r
> experience and tell if anything goes wrong.

 Without commenting on overall feedback arrangement.

A shown IC1A output totally swamps the smoothed PWM signal.
If the opamp was ideal the PWM would have no effect at all.
As shown the drove through R2 is "combatted" by the op amp. As the PWM
current will be well under 1 mA the op amp will do quit well at
resisting it and holding C27 constant.



Russell
--=20
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